Reverse-current indicator.



No. 743,417. PATENTED NOV. 10, 1903.

L. ANDREWS. REVERSE CURRENT INDICATOR.

APPLIGATIOiI FILED MAR. 30. 1903.

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UNITED STATES LEONARD ANDREWS, or HASTINGS,

Patented November 10, 1903.

PATENT OFFICE.

ENGLAND, ASSIGNOR TO STANLEY ELECTRIC MANUFACTURING COMPANY, OFPITTSFIELD', MASSACHU- SETTS, ACORPORATION OF NEW JERSEY.

REVERSE-CURRENT INDICATOR.-

SPEQIFIOATION forming part of Letters Patent No. 743,417, dated November10, 1903.

Application filed March 30,1903.

To all whom it may concern.-

Be it known that I, LEONARD ANDREWS, a subject of the King of GreatBritain and Ireland, residing at Hastings, in the county of Sussex,England, have invented Improvements in Reverse-CurrentIndicators,ofwhich the following is a specification.

' current.

This invention relates to apparatus adapted forindicating or for openingor closing a circuit on change of the direction ofthe flow of electricalenergyin the form of alternating An apparatus according theretocomprises a transformer-core forming two magnetic circuits magneticallyconnected together, two secondaries arranged to be energized by said twocircuits, respectively, a primary arranged to produce fluxes in both ofsaid circuits simultaneously, and a primary arranged to influence saidfluxes, so as to oppose one and assist the other. The circuits of thetwo secondaries may be either provided with means for-producing separateindications or be adapted to produce a single indication resulting fromtheir mutual cooperation. The transformer has or may have a core with acentral member which carries one primary winding and which has at itsends two cross members which each extend in opposite directions from thecentral member and are magnetically connected together at their ends andof which one carries equally on its parts projecting on opposite sidesof the central member a winding for the other primary, while the othercross member carries the two secondaries disposed one on each side ofthe central member. Such a transformer comprises two magnetic circuitsunited for a portion of their length and adapted to be mutuallyenergized by the primary winding surrounding their'united portions andother windings, of which one (a primary) is divided between and adaptedto influence the two magnetic circuits on their ununited portions, whilethe remaining windings are respectively located upon the ununitedportions of the two magnetic circuits and admi d to supplyindicating-currents. It will be clear from this that the'conductors onthe ununited portions of the magnetic circuits may be severally locatedin any desired positions and are not re- I Serial No. 160,317. (Nomodel.)

to produce equal indicating-currents in the.

conductors therefor, while the other primary will tend to increase theflux in one magnetic circuit and. decrease it in the other, the magneticcircuit having the greater flux and producing the controlling or thegreater indicating current being liable to change with change in therelative directions of the currents in the primaries.

The indication may be ous ways. separate windings adapted to furnishindicating-current are connected to lamps. It maybe colored red andgreen, respectively. the arrangement being such that unlesscurrentsflowin both of the primaries neither of the lamps will be lighted, butthat if currents flow inboth in the proper relative difurnished in vari-According to one arrangement rections the green lampwill light, while ifto one of a number of alternating-current generators connected inparallel to a pair of bus bars. In each example 1 and 2 are thebus-bars. 3 is the generator. 4 and 5 are the conductors leading fromthe generator 3 to the bars 1 and 2, respectively. 6 is the core of thetransformer. 7 and 8 are two indicating lamps arranged, respectively, insecondary conductors 9 and 10, and 11 is a conductor connecting togetherthe two bars 1 and 2. It will be seen that'the transformers core, ashereinb'efore described, forms two magnetic circuits 12 andl3, which areunited for a portion 14 of the length of each. In the example shown inFig. 1 the conductor 5 is wound round an ununited portion of each of IOCI the case.

the circuits l2 and 13, while the conductor 11 is wound upon the unitedportions 14; but in the example shown in Fig. 2 the reverse is In eachexample the secondary conductors 9 and 10 are wound upon ununitedportions of the two circuits 12 and 13. The arrows attached to theprimaries 5 and 11 indicate the directions of the currents flowingtherein when the generator is supplying energy to the bus-bars -1 and 2.When the currents are flowing in the conductors 5 and 11 in thedirections indicated, they tend,

respectively, to induce magnetic fluxes in the core of the transformerin the directions indicated by the arrows marked a and I), respectively.It will be seen that the fluxes due to the primaries oppose each otherin the circuit 12, and consequently the lamp 7 of the secondary 9 woundthereon is not lighted, whereas the flux due to the two primaries assisteach other in the circuit 13, and consequentiy induce sufficient currentin the secondary l0 wound thereon to light the lamp 8. It will beobvious that the simultaneous reversal of the currents in the conductors5 and 11 due to the mere'alternation of current in the system willhaveno effect on the lamps 7 and 8. Should the generator-curerator from thebus-bars, which are excited by the other generators, and the directionofthe flux produced by the conductor 5 would be reversed in relation tothat produced by the conductor 11, so that the lamp 8 would beextinguished arid the lamp 7 would be lighted.

Instead of connecting the two bus-bars together directly the conductor11 might obviouslyloe arranged to have current induced in it by thecurrent in the bus-bars. Again, instead of connecting the primary of thecon 'dnctor 11 to the bars 1 and 2 it might be connected to theconductors 4 and 5 at points between the generator 3 and the transformerand between the generator and the bar 1, respectively.

It will be seen that the primary of the conductor 5 and the primary ofthe conductor 11 are respectively in series with and a shunt to thecircuit of the generator 3; but the reverse might be'the case 1 What Iclaim is- 1. The combination of a transformer-core forming two magneticcircuits magnetically connected together, two secondaries arranged to beenergized by said two circuits respectively, a primary arranged toproduce fluxes in both of said circuits simultaneously anda primaryarranged to influence said fluxes so as to oppose one and assist theother.

' 2. The combination with an electrical circuit, of atransformer-coreforming two magnetic circuits magnetically connectedtoget'her, two secondaries arranged to-be energized by said two circuitsrespectively, a primary arranged to produce fluxes in both of saidcircuits simultaneously, and a primary arranged to'influence said fluxesso as to 0p pose one and assist the other, one of said primaries beingconnected in series with said electrical circuit and the other of saidprimaries being a shunt 'thereto.

3. The combination of a transformer-core forming two magnetic circuitsunited for a portion of the length of each of them, and four windings,namely. a winding round the united portions of said circuits, a windinground the ununited portion of each of said circuits, and a windingpartly round the ununited portion of one of said circuits and partlyround the un united portion of the other of said circuits.

4. The combination of a transformer-core forming two magnetic circuitsunited for a portion of the length of each of them, a winding round theunited portions of said circuits, a winding partly round the ununitedportion of one of said circuits and partly round the ununited portion ofthe other of said circuits, conductors also wound upon said core so asto' be under the influence of the magnetic fluxes produced by currentsflowing in said windings and electroresponsivedevices connected to theterminals of said conductors. rent fall, current will flow to thefailing gen-' 5. The combination of a transformer-core forming twomagnetic circuits united for a portion of the length of each of them, awinding round the united portions of said circuits, a winding partlyround the ununited portion of one of said circuits and partly round theununited portion of the other of said circuits, conductors also woundupon said core so as to be under the influence of the magnetic fluxesproduced by currents flowing in said windings, and a lamp or othersignaling device connected in the circuit of each'of said conductors.

6. The combination of a transformer-core forming two magnetic circuitsunited for a portion of the length of each of them, four windings,namely a winding round the united portions of said circuits, a windinground-the ununited portion of each of said circuits, and

1 a winding partly round the ununited-portion of one of said circuitsand partly round the ununited portion of the other of said circuits, anda lamp or other signaling device connested in the circuit of each ofsaid windings wound round the ununited portion of only one of saidcircuits.

7. In combination, two magnetic circuits, two secondaries arranged to beenergized by said two circuits respectively, a primary arranged toproduce fluxesimboth 'of said cir- IIO cuits simultaneously, a primaryarranged to Y influence said fluxes so as to oppose one and assist theother, and electroresponsive devices connected to said secondaries.

- '8.v In combination, two magnetic circuits, two secondaries arrangedto be energized by said two circuits respectively, a primary ar rangedto produce fluxes in both of said circuitssimultaneously, and a primaryarranged.

to influence said fluxes so as to oppose one and assist the other.

9. In combination, an electrical circuit, two magnetic circuits, twosecondaries arranged to be energized by said two circuits respectively,a primary arranged to produce fluxes in both of said magnetic circuitssimultaneously, a primary arranged to influence said fluxes so as tooppose one and assist the other, one of said primaries being connectedin serieswgith said electrical circuit and the other of said primariesbeing inshunt thereto.

10. In combination, an electrical circuit, two-magnetic circuits, twosecondaries ari5 ranged to be energized by said two magnetic circuitsrespectively, indicating devices connected to said secondaries, aprimary arranged to produce fluxes in both of said magnetic circuitssimultaneously and a primary arranged to influence said fluxes so as tooppose one and assist the other, one of said primaries being connectedin series with said electrical circuit and the other of said primariesbeing in shunt thereto.

Signed at 75-77 Cornhill, London, England, this 18th'day of March, 1903.

- LEONARD ANDREWS.

Witnesses:

PERCY E. MA'ITOOKS, WM. 0. BROWN.

